As is known in the art, a bearing is a device which allows constrained relative motion, typically rotation or linear movement, between two parts or objects. Bearings may be classified broadly according to the motions they allow and according to their principle of operation as well as by the directions of applied loads they can handle.
A hinge is a type of bearing that connects two objects, typically allowing only a limited angle of rotation between the objects. Two objects connected by an ideal hinge rotate relative to each other about a fixed axis of rotation (the geometrical axis of the hinge). Hinges may be made of rigid or flexible material and/or of moving components. Hinges are employed in many types of doors, movable bridges, furniture, electronics, automobile doors or in any structure which it is desirable to have two objects connected but which can rotate relative to each other.
A translating hinge is a particular type of hinge which allows both a translating motion and a rotation. Two techniques have conventionally been used to provide translating hinges. One technique utilizes four bar linkages and another technique utilizes slotted hinge assemblies. Some of the drawbacks of the four bar linkage techniques are: (1) the resulting hinge does not translate in a direction which is perpendicular to a mating surface; (2) the resulting hinge has many moving parts; (3) the resulting hinge is a relatively bulky assembly and thus limits the locations/applications in which the hinge can be used. Some of the drawbacks of the slotted hinge techniques are: (1) rotation can occur before translation is complete (which could be undesirable in some applications which require translation to be complete prior to rotation); (2) the resulting hinge is relatively difficult to spring load at the translated position; and (3) tight tolerances are relatively difficult to achieve due to the precision with which a slot can be provided in the hinge structure since in general, fabrication of slots is typically accomplished by interpolating an outer profile of the slot with an end mill of a smaller diameter than the slot width. Slots provided using this technique struggle to achieve tolerances greater than +/−0.002 in. especially when the ratio of slot depth to end mill diameter exceeds 5 to 1.